The iron-nickel oxides, he said, have higher catalytic activity than the precious-metal-based catalytic materials that have been thought to be the best for the job.
"What we found is that when we take nickel oxide films that start out as a crystalline material with the rock-salt structure like table salt, they absorb iron impurities and spontaneously convert into materials with a layered structure during the catalysis process," Boettcher said.
Lena Trotochaud, a doctoral student and lead author on both papers, studied this process and how the films can be combined with semiconductors. "The semiconductors absorb the light, generating electron-hole pairs which move onto the catalyst material and proceed to drive the water-splitting reaction, creating fuel," Boettcher said.
The computer modeling was used to understand how the amount of sunlight that the catalyst blocks from reaching the semiconductor can be minimized while simultaneously speeding up the reaction with water to form oxygen gas. This basic discovery remains a lab accomplishment for now, but it could advance to testing in a prototype device, Boettcher added.
"We're now looking at the fundamental reasons why these materials are good," Trotochaud said. "We are trying to understand how the catalyst works by focusing on the chemistry that is happening, and then also recognizing how that fits into a real system. Our research is fundamentally guiding how you would take these catalysts and incorporate them into some
|Contact: Jim Barlow|
University of Oregon